Stain removal

ABSTRACT

Composition for removing stains from fabrics, including, an enzyme, a per-compound, and an activator for the perborate.

United States Patent Gray Jan. 25, 1972 l 5 4] STAIN REMOVAL [72] Inventor: Frederick William Gray, 14 Stockton Road, Summit, NJ. 07901 [52] [1.8. CI. ..8/lll, 252/95, 252/96, 252/97, 252/98, 252/99, 252/186 [51] Int. Cl. ..D0613/02 [58] Field of Search ..282/99, 98, 97, 96, 95, 186; 8/1 11 56] References Cited UNITED STATES PATENTS 2,152,520 3/1939 Lind "25 2 99 2,287,064 6/1942 Reichert et a1. ..,.....252/1 86 2,898,181 8/1959 Dithmar et a1 ....252/99 X 3,061,550 10/1962 Baevsky ..8/1l1 X 3,163,606 12/1964 Vivern ..252/99 3,183,266 5/1965 Matiner 252/97 X 3,425,786 2/1969 Dithmar ..8/1 11 Primary Examiner-Mayer Weinblatt Attorney-Herbert S. Sylvester, Murray M. Grill, Norman Blumenkopf, Ronald S. Cornell, Thomas J.Corum, Richard N. Miller and Robert L. Stone [57] ABSTRACT Composition for removing stains from fabrics, including, an enzyme, a per-compound, and an activator for the perborate.

21 Claims, No Drawings taught that the presence of the perborate has an inhibitory effeet on the enzyme action, which inhibitory action passes away, in part, after some time (e.g., on soaking overnight in the presence of the detergent composition). The use of bleaches of greater activity than sodium perborate, such as chlorine bleaches (supplied for instance by the use of a chloroisocyanurate material which yields hypochlorous ions in the wash water) has a marked inhibiting effect on the stainremoving activity of detergent products containing enzymes.

in accordance with one aspect of this invention there is provided a novel and highly effective composition for use in the washing of clothes comprising a mixture of a proteolytic enzyme, sodium perborate, and an activator for the perborate. Surprisingly, in the presence of the activator one can obtain, in a short washing cycle, and at a moderate washing temperature, not only improved bleaching of those stains (e.g., coffee and tea stains) as are usually afi'ected by bleaching compositions but also the removal of proteinaceous stains to an extent equal to or better than is obtained when the perborate and activator are omitted.

The proteolytic enzymes which are employed in the instant invention are active upon protein matter and catalyze digestion or degradation of such matter when present as in linen or fabric stain in a hydrolysis reaction. The enzymes are effective at a pH range of about 4-12, such as usually prevails in detergent cleaning procedures. Moreover, they may be effective even at moderately high temperatures so long as the temperature does not degrade them. Some proteolytic enzymes are effective at up to about 80 C. and higher. They are also effective at ambient temperature and lower to about 10 C. Particular examples of proteolytic enzymes which may be used in the instant invention include pepsin, trypsin, chymotrypsin, papain, bromelin, colleginase, keratinase, carboxylase, amino peptidase, elastase, subtilisia and aspergillopepidase A and B. They are available also under names such as Alcalase (Novo lndustri, Copenhagen, Denmark), Monzyme (Monsanto Chemical Co.), Maxatase (Royal Netherlands Fermentation, Delft, Netherlands), Protease AP (Sandoz-Ferment, Basle, Switzerland). Protease 8-400 (Sandoz- Ferment), Protease ATP 40 (Sandoz-Ferment), Pancreatin NF (Pfizer), Pancreatin 6xNF (Armour), Fungal Protease (Miles), DSE Numbers 4-9 (Rohm and Haas), Exzyme 'DPX (Premier Malt), Protease 14-252 Digester (Premier Malt), Protease L-253 Digester (Premier Malt), Protease 1-423 (Premier Malt), Protease L-516 (Premier Malt), Protease L-517 (Premier Malt), Texzyme PX-l (Premier Malt), Protease P-G (Pfizer), Compound 37B (Miles), Serizyme (Wallerstein), Papain 100 (Wallerstein), Optimo Papain (Penick), Ficin (Miles), Bromelain (Miles), HT Proteolytic Concentrate (Miles), Protease ATP 40 (Rapidase), Protease ATP 120 (Rapidase), Rhozyme P-ll (Rohm and Haas), and Rhozyme PF (Rohm and Haas).

Proteolytic enzymes such as Alcalase, Maxatase, Protease AP, Protease ATP 40, Protease ATP 120, Protease L-252 and Protease L-423 are derived from strains of spore-forming bacillus, such as Bacillus subtillis.

Different proteolytic enzymes have different degrees of effectiveness in aiding in the removal of stains from textiles and linen. Particularly preferred as stain-removing enzymes are Alcalase, Maxatase, Protease AP, Protease ATP 40, and Rapidase.

Metalloproteases which contain divalent ions such as calcium, magnesium or zinc bound to their protein chains are of particular interest.

The perborate activators are a well-known class of materials, described for example in a series of articles by Gilbert in Detergent Age, June 1967 pp. 18-20, July 1967 pp. 30-33, and Aug. 1967 pp. 26, 27, and 67. The perborate activators of greatest importance in the practice of this invention are compounds which are percarboxylic acid precursors. As explained by Gilbert, such compounds include esters and anhydrides and acyl amides. Examples of suitable activators are given by Gilbert who also described a test for suitability. Among the activators which may be used are the following:

N-acetyl phthalimide N-acetyl succinimide Triascetyl cyanurate N-benzoyl'succinimide Phenyl acetate Acetylsalicylic Acid N-p-anisoyl succinimide N-alpha-napthoyl succinimide N-beta-napthoyl succinimide N-benzoyl glutarimide N-p-chlorobenzoyl succinimide N-benzoyl succinimide N-p-chlorobenzoyl-S,S-dimethyl hydantoin N-o-chlorobenzoyl succinimide N-p-chlorobenzoyl phthalimide etc.

Further examples of suitable activator compounds of the imide type, both cyclic and aliphatic, have the following structural formula:

wherein X represents halogen, e.g., chloro and Z represents the atoms necessary to complete a heterocyclic nucleus selected from the group consisting of hydantoin and succinimide.

Specific representatives of compounds of this type include, without necessary limitation, the following:

N-m-chlorobenzoyl-5,5-dimethyl hydantoin N-m-chlorobenzoylsuccinimide etc. Another group of activator compounds comprises N-sulfonated cyclic imides including those of the following struclural formula:

wherein R represents lower alkyl of from one to four carbon atoms and aryl and Z represents the atoms necessary to complete a heterocyclic ring selected from the group consisting of succinimide and phthalimide. Specific examples of compounds of this type include, without necessary limitation, the following:

N-benzenesulfonyl phthalimide N-benzenesulfonyl succinimide N-methanesulfonyl phthalimide N-methanesulfonyl su ccinimide A further class of activator compounds comprises alkyl and aryl chloroformate derivatives, including for example:

methylchloroformate ethylchloroformate phenylchloroformate The proportions of per-compound, activator, and enzyme will be influenced by the physical and chemical properties of these ingredients, the time and temperature of the bleaching or laundering operation, and the degree of bleaching desired.

A preferred range of proportions of the perborate is one which provides a concentration of per-compound in the wash water equivalent to about 1 to 40 ppm. more preferably about 4 to 25 ppm. e.g., 8 to 20 ppm. of available oxygen; about 20 ppm. has thus far given best results. In sodium perborate tetrahydrate (NaBO -4H O) the available oxygen content (or peroxy oxygen content) is about percent; i.e., one atom of available oxygen per molecule of the perborate. The proportions of perborate for use in the detergent formulation can therefore readily be calculated if one knows how much of the total formulation is to be added to the wash water. Commercial detergent formulations are often designed for use in proportions in the range of about 0.1-0.2 percent in the wash water (e.g., at 0.15 percent concentration), a preferred detergent formulation containing sodium perborate tetrahydrate designed for use at the 0.15 percent concentration in the wash water will therefore contain approximately 5 to percent of that compound, correspondingly roughly to the 8 to ppm. of available oxygen.

Since individual activators vary in structure and molecular weight as well as performance, it is convenient to relate the quantity of activator to be employed to the desired available oxygen present in the particular per-compound being used. For reactive aromatic monoacyl compounds ,such as metachlorobenzoyIdimethylhydantoin and metachlorobenzoylsuccinimide, strong bleaching is obtained when approximately equimolecular quantities of activator and peroxygen are present. Bleaching is enhanced with increase in the concentration of activator and maintenance of about a 1:1 mol ratio of activator and the peroxygen present in the percompound. By increase of the mol ratio of available oxygen to activator, milder bleaching is obtained particularly when the ratio is greater than 2:1. For reactive aliphatic polyacylated compounds such as tetra-acetyl ethylenediamine, tetra-acetyl hydrazine, triacetyl cyanurate, the mole ratio of available oxygen to activator is preferably 2:1, although higher (e.g., 6:1) or lower (e.g., about 1:1 or less) mol ratios may be employed.

The enzyme concentration can be varied widely, Typically the enzyme is present in amount in the range of about 0,001-4 percent by weight of the total detergent fonnulation, preferably in the range of about 0.05-1 percent and most preferably in the range of about 0.1 to 0.5 percent. The uptimum proportion of enzyme to be used in a detergent composition containing per-compound and activator will of course depend upon the effective enzyme content of the enzyme preparation. As with per-compound content, the quantity of enzyme to be used for stains susceptible to enzyme action will be dependent upon a number of factors, particularly time, temperature, and proportions of per-compound and activator. For the enzyme sold as Alcalase (having an activity of about 1.5 Anson units per gram) a preferred range of proportions is one which gives about 1 to 40 p'.p.m., more preferably about 2-8 ppm, of the Alcalase in the wash water. This 2-8 p.p.m. concentration corresponds to about 0.003-0.0l2 Anson units per liter of wash water or, in a detergent formulation designed for use at a concentration of 1.5 gram per liter of wash water, about 0.0020.008 Anson units per gram of detergent formulation.

The enzyme, perborate and activator may be used together, as in the water used for a prerinse of the soiled clothes, without any surface-active detergent being present. It is preferable, however, to mix these ingredients into a surfaceactive detergent composition, such as a heavy-duty built granular detergent composition.

The surface-active agent which may be employed may be any commonly used compound having surface-active or detergent properties. Most preferred are those water-soluble surface-active compounds having anionic or nonionic properties. Anionic surface-active agents include those surface active or detergent compounds which contain an organic hydrophobic group and an anionic solubilizing group. Typical example of anionic solubilizing groups are sulfonate, sulfate, carboxylate, and phosphate. Examples of suitable anionic detergents which fall within the scope of the invention include the soaps, such as the water-soluble salts of higher fatty acids or rosin acids, such as may be derived from fats, oils and waxes of animal, vegetable or marine origin, e.g., the sodium soaps of tallow, grease, coconut oil, tall oil and mixtures thereof; and the sulfated and sulfonated synthetic detergents, particularly those having about eight to 26, and preferably about 12 to 22, carbon atoms to the molecule.

As examples of suitable synthetic anionic detergents there may be cited the higher alkyl mononuclear aromatic sulfonates such as the higher alkyl benzene sulfonates containing from 10 to 16 carbon atoms in the alkyl group in a straight or branched chain, e.g., the sodium salts of decyl, undecyl, dodecyl (lauryl), tridecyl, tetradecyl, pentadecyl, or hexadecyl benzene sulfonate and the higher alkyl toluene, xylene and phenol sulfonates; alkyl naphthalene sulfonate, ammonium diamyl naphthalene sulfonate, and sodium dinonyl naphthalene sulfonate, sulfated aliphatic alcohols such as sodium lauryl and hexadecyl sulfates, triethanolamine lauryl sulfate, and sodium oleyl sulfate; sulfated alcohol ether, such as lauryl, tridecyl, or tetradecyl sulfates including two to four ethylene oxide moieties; sulfated and sulfonated fatty oils, acids or esters such as the sodium salts of sulfonated castor oil and sulfated red oil; sulfated hydroxyamides such as sulfated hydroxylethyl lauramide; sodium salt of lauryl sulfoacetate; sodium salt of dioctyl sulfosuccinate; and the sodium salt of oleyl methyl tauride.

Other anionic surface-active agents which may be employed in the practice of this invention include olefin sulfonates, typically containing eight to 25 carbon atoms.

Also included within the ambit of the invention are the sulfuric acid esters of polyhydric alcohols incompletely esterified with higher fatty acids, e.g., coconut oil monoglycen'de monosulfate, tallow digylceride monosulfate; and the hydroxy sulfonated higher fatty acid esters such as the higher fatty acid esters of low-molecular weight alkylol sulfonic acids, e.g., oleic acid ester of isethionic acid.

Nonionic surface-active agents are those surface active or detergent compounds which contain an organic hydrophobic group and a hydrophilic group which is a reaction product of a solubilizing group such as carboxylate, hydroxyl, amido, or amino with ethylene oxide or with the polyhydration product thereof, polyethylene glycol.

As examples of nonionic surface-active agents there may be noted the condensation products of alkyl phenols with ethylene oxide, e.g., the reaction product of .isooctyl phenol with about six to 30 ethylene oxide units; condensation products of alkyl thiophenols with 10 to 15 ethylene oxide units; condensation products of higher fatty alcohols such as tridecyl alcohol with ethylene oxide; ethylene oxide addends of monoesters of hexahydric alcohols and inner ethers thereof such as sorbitan monolaurate, sorbitol mono-oleate and mannitan monopalmitate and the condensation products of polypropylene glycol with ethylene oxide.

Cationic surface-active agents may also be employed. Such agents are those surface-active detergent compounds which contain an organic hydrophobic group and a cationic solubilizing group. Typical cationic solubilizing groups are amine and quaternary groups.

As examples of suitable synthetic cationic detergents there may be noted the diamines such as those of the type RNHC H NH wherein R is an alkyl group of about 12 to 22 carbon atoms, such as N-aminoethyl ste'aryl amine and N- aminoethyl myristyl amine; amide-linked amines such as those of the type RCONllC H Nl-l wherein R' is an alkyl group of about 12 to 18 carbon atoms, such as N-amino ethyl-stearyl amide and N-amino ethyl myristyl amide; quaternary ammonium compounds wherein typically one of the groups linked to the nitrogen atom is an alkyl group of about 12 to 18 carbon atoms and three of the groups linked to the nitrogen atom are alkyl groups which contain one to three carbon atoms, including such one to three carbon alkyl groups bearing inert substituents, such as phenyl groups, and there is present an anion such as halogen, acetate, methosulfate, etc. Typical quatemary ammonium detergents are ethyl-dimethyl-stearyl ammonium chloride, benzyl-dimethyl-stearyl ammonium chloride, benzyl-dimethyl-stearyl ammonium chloride, trimethyl-stearyl ammonium chloride, trimethylcetyl ammonium bromide, methyl-ethyl-dilauryl ammonium chloride, dimethyl-propylmyristyl ammonium chloride, and the corresponding methosulfates and acetates.

The surface-active compounds which are used in the most preferred aspects of this invention are those having anionic or nonionic properties. The most highly preferred water-soluble anionic detergent compounds are the ammonium and substituted ammonium (such as mono-, di-, and triethanolamine), alkali metal (such as sodium and potassium) and alkaline earth metal (such as calcium and magnesium) salts of the higher alkyl benzene sulfonates, the higher alkyl sulfates, and the higher fatty acid monoglyceride sulfates. The particular salt will be suitably selected depending upon the particular formulation and the proportions therein.

The surface-active agent is typically present in amount of about 5-95 percent by weight of the detergent composition, preferably -25 percent by weight.

The enzyme may be present in powdered form admixed into the detergent formulation.

In addition to the materials described above, the detergent composition of the invention may include a builder for the detergent. The builder may be any of the water-soluble inorganic builder salts commonly known in the art, or it may be a watersoluble organic sequestering agent such as sodium nitrilotriacetate, or mixtures thereof.

The water-soluble inorganic builder salts may be suitable alkali metal, alkaline earth metal, or heavy metal salt or combinations thereof. Ammonium or an ethanolammonium salt in a suitable amount may be added also, but generally the sodium and potassium salts are preferred. Examples are the watersoluble sodium and potassium phosphates, silicates, carbonates, bicarbonates, borates, sulfates and chlorides. Particularly preferred builder salts are the alkaline builder salts such as polyphosphates, silicates, borates, etc.

In the water-soluble inorganic builder salt mixtures used in the detergent compositions, it is often preferred to have present a mixture of sodium tripolyphosphate and sodium or potassium bicarbonate, such as a combination or mixture of salts wherein the bicarbonate to tripolyphosophate ratio is selected from the range of about 1:1 to about 3: 1.

Both phase I and phase 11 sodium tripolyphosphate and mixtures thereof may be successfully used in the compositions. The usual commercial tripolyphosphate consists mainly of the phase ll material. The commercial tripolyphosphate material is usually essentially tripolyphosphate, e.g., 87-95 percent, with small amounts, e.g., 4-l3 percent of other phosphates,

e.g., pyrophosphate and orthophosphate. Sodium tripolyphosphate in its hydrated form may be used also. Trisodium orthophosphate may be used in the amounts indicated.

The sodium or potassium bicarbonate is an effective pH buffer. The bicarbonate may be incorporated directly as anhydrous bicarbonate or in the form of sesquicarbonate, a hydrate containing both bicarbonate and carbonate.

Other suitable builder salts which may be present include the water-soluble sodium and potassium silicates, carbonates, borates, chlorides, and sulfates.

Generally, when present the builder salt is employed in amount in the range of about 20-90 percent, preferably at least 25 percent, (e. g., 35 to 80 percent) of the detergent composition.

The composition may also contain polymeric additives such as sodium carboxymethylcellulose or polyvinyl alcohol (e.g., in amount of about 0.1-5 percent) or other polymeric additives to inhibit redeposition of soil. Minor amounts of optical brighteners may be present, as in proportions in the range of about 0.01 to 0.15 percent; examples of such brighteners are the stilbene brighteners such as sodium-2-sulfo-4-( Z-naphtho- 1,2triazole) stilbene; disodium 4,4-bis(4-anilino-6- morpholino-s-triazin-Z-yl amino) stilbene disulfonate or disodium 4,4-bis(4,6-diani]ino-s-triazin-Zyl-amino) stilbenedisulfonate; and the oxazole brighteners, having for example a l-phenyl-2-benzoxazole ethylene structure. Per fumes, coloring agents, and preservatives may also be included.

The activator, enzyme and perborate may be added in powdered form to the detergent composition and mixed therewith, as by dry blending. To improve the stability of the compositions, one or more of these ingredients may be protected from the atmosphere or from contact .with the others. For instance, the perborate or the activator or the enzyme or each of them may be encapulated or agglomerated by means of a coating of a protective material such as polyvinyl alcohol, a long chain fatty acid (e.g., lauric or stearic) or an amide thereof, a paraffin or a water-soluble or water-dispersible polyethylene glycol (e.g., a solid Carbowax"). It is also within the broader scope of the invention to supply separate packets (e.g., in moistureproof wrappings) of these ingredients for addition to the wash water.

The compositions of this invention may be used for washing for short periods, e.g., 5 to 45 minutes, in cool water, e.g., at Q-100- E .9r in warm or hot water, e.g., at 110, 120 140,

- or 160 F., or even at or near the boil. They may alsoTif desired, be used for long period soaking at room temperature or in hot water, e.g., for soaking several hours or overnight.

The following examples are given to illustrate this invention further. In these examples, as in the rest of the application, all proportions are by weight unless otherwise indicated.

EXAMPLE 1 A. A detergent composition contains the following ingredients: 10 percent nonionic detergent consisting of a primary alkanol of an average of 14 to 15 carbon atoms ethoxylated with an average of l 1 mols of ethylene oxide per mol of alkanol (Shell Neodol 45-11); 30 percent anhydrous pentasodium tripolyphosphate (designated TPP below); 5 percent trisodium 1 nitrilotriacetate monohydrate (designated NTA below); 0.5 percent sodium carboxymethyl cellulose (designated CMC below); 0.8 percent of the commercial proteolytic enzyme preparation known as Alcalase"; 16 percent of sodium perborate (NaBO -4H O); 24 percent of metachlorobenzoyldimethylhydantoin (an activator for the perborate); the balance sodium sulfate. In this composition the mol ratio of perborate to activator is about 1:1 (specificallyitis 1.1:1).

The composition is used for the washing of standard cocoastained fabrics and standard coffee/tea-stained fabrics at F. for a period of 10 minutes, using 1 gram of the composition per liter of water in a Terg-O-Tometer. The effectiveness of the composition is determined by reflectance readings (R,,,) on the fabrics before and after washing, using a Gardner Color Difference Meter for the measurement. The difference in reflectance before and after the washing is reported as AR Cocoa is a proteinaceous substance and cocoa-stained fabric is a commonly used material for testing the effectiveness of detergents for removing protein stains.

For comparison the same washing tests are made on otherwise identical compositions, (B) containing no enzyme, perborate or activator; (C) containing enzyme, but no perborate or activator; and (D) containing the enzyme plus a commercial bleach yielding hypochlorous ion (specifically a mixture of 4/5 potassium dichloroisocyamurate (KDCC) and 1/5 trichloroisocyanuric acid (TCCA). The results are tabulated below:

Composition A B C D Detergent 10% 10% 10% 10% TPP 30% 30% 30% 30% NTA 5% 5% 5% CMC 0.5% 0.5% 0.5% 0.5% Alcalitsc" 0.8% 0 8% 0.8% Perboratc 16% Activator 24.8%

KDCC-TCCA 18.1% Na,SO, 0.5. 0.8. 0.5. 0.8.

For cocoa-stained fabric +13.4 +7.6 +ll.0 +4.8 For coffee/teastaincd fabric +8.0 0.1 +0.4 +8.2

EXAMPLE 2 In this example an enzyme, sodium perborate and activator are dry-blended with a spray-dried detergent fonnulation having the following composition: sodium linear tridecylbenzenesulfonate 12.6 percent (active ingredient); sodium tallow alcohol sulfate 11.6 percent (active ingredient); TPP 35.8 percent; sodium silicate (of 1:2.35 Na O:SiO ratio) 6.3 percent; CMC 0.5 percent; polyvinyl alcohol 0.2 percent; water (including water of hydration) 8.9 percent; Na SO balance. Two blends are prepared, of the following compositions, in parts by weight:

Composition A B Spray-dried detergent formulation 1.5 1.5

Alcalase 0.008 Monzymc 0.002

sodium perborate 0.16 0.16 activator ofex. 1 0.248 0.248

EXAMPLE 3 Examples 2A and B are repeated except that the spray-dried detergent has a different composition and is made in the following manner: In a crutcher there are mixed in the order given 139 parts of water, 213 parts of an aqueous slurry containing about 44 percent sodium linear tridecylbenzenesulfonate, 109.3 parts of anhydrous sodium sulfate, 4.4 parts of borax, 0.13 part of phenolic antioxidant (lphol 033), 71.4 parts of aqueous sodium silicate of 43.5 percent concentration (in which the Na O:SiO mol ratio is 1:2.35), and 157 parts of anhydrous pentasodium tripolyphosphate. The aqueous mixture is spray dried to give a granular composition of the foregoing ingredients having a total moisture content of about 8% percent (including water of hydration).

EXAMPLE 4 1n this example there are used compositions as described in example 1A, except that the activator is (A) 1 1.9 percent of tetra acetyl ethylene diamine or (B) 10.4 percent tetra-acetyl hydrazine, or (C) 13.3 percent triacetylcyanurate. For comparison there are also used compositions (D) containing no activator and (E) containing no activator or perborate.

The compositions are used for the soaking of standard cocoa-stained and standard coffee/tea-stained fabrics, using 1 gram of the composition per liter of water. The water is initially at F. and cools to room temperature (about 76 F.) during the soaking period, which is continued for 18 hours. The test fabrics are removed and dried and the AR,, values are obtained.

The results are tabulated below:

Pcrborate: activators mol ratio 2:1 2:1 2:1 no activator M1 50 0.8. 0.5. OS. 0.8. 0.8.

For cocoastained fabric 10.1 +10.9 +131 +5.2 +l0.2

For coffee/teastained fabric +5.9 +5.5 +6.5 +1.7 +2.7

These results indicate that the addition of the perborate to an enzyme-containing composition in a soaking test gives poorer results, both for the protein-containing stain and the coffee/tea stain, than when perborate is absent. The addition of the activator improves the stain removal not only for the coffee/tea stain but also for the protein stain.

A composition prepared as in example 4A is storage-tested by subjecting it for 3 days to a temperature of 120 F. in a sealed container. During this period there is little, if any, undesirable odor developed. Soaking tests with standard cocoastained and coffee/tea-stained fabrics give substantially identical results for the composition before the 3-day aging at 120 F. and after such aging.

EXAMPLE 5 Three separate compositions are prepared as in example 1A, using tetra-acetyl ethylenediamine (i.e., N,N,N'N-tetraacetyl ethylenediamine) as the activator in each case, with the following other changes:

A. The amount of activator is changed to 1 1.9 percent and the amount of TPP is changed to 54.5 percent.

B. The amount of activator is changed to 8.9 percent and the amount of perborate is changed to 12.0 percent.

C. The amount of activator is changed to 7.4 percent and the amount of perborate is changed to 10.0 percent.

EXAMPLE 6 81.8 parts of a spray-dried built detergent formulation are mixed with 0.8 part of Alcalase, 7.4 parts of tetra-acetyl ethylenediamine and 10 parts of sodium perborate. The spraydried formulation contains 10.5 percent sodium linear tridecylbenzene-sulfonate, l percent pentasodium tripolyphosphate, 6 percent sodium silicate (Na O:SiO mol ratio 1235), 8.5 percent sodium chloride, 13 percent sodium sulfate, percent moisture (including water of hydration) and about 1 percent fluorescent brighteners.

The resulting composition is tested, using the washing tests described in example 1. The results, in terms of AR,,,, for the cocoa-stained and cofiee/tea-stained fabrics are found to be substantially better than those for the same tests using the same composition except that no perborate or activator is present (these being replaced by an equal weight of sodium sulfate); the latter results are in turn substantially better (in terms of removal of cocoa stain) than when the same composition is used without any enzyme, perborate or activator (these being replaced by an equal weight of sodium sulfate).

The composition is also given a soaking test, as described in example 4. The results, in terms of AR for the cocoa-stained and coffee/tea-stained fabrics are found to be substantially better than those for the same tests using the same composition except that no perborate or activator is present (these being replaced by an equal weight of sodium sulfate); the latter results are in turn substantially better than when the same composition is used without any enzyme, perborate or activator (these being replaced by an equal weight of sodium sulfate). In the same type of soaking test, made after the compositions have been aged for 3 days at 120 F. in sealed containers, a similar superiority for the enzyme-containing composition with perborate plus activator is observed.

EXAMPLE 7 Example 1A is repeated, except that the composition contains 100 parts of the detergent of example 1, 300 parts of the TPP, 50 parts of the NTA, 5 parts of the CMC, 240 parts of the sodium perborate and 371 parts of m-chlorobenzoylsuccinimide as the activator.

EXAMPLE 8 Example 1A is repeated using, in place of the activator and perborate, 25 percent of solid m-chloroperbenzoic acid.

EXAMPLE 9 Example 4 is repeated, except that the amount of the perborate is 8 percent and the activator is m-chlorobenzoyldimethylhydantoin,present in amount of 13.9 percent (a 1:1 perborate: activator mol-ratio) AR, values of +l5.4 .(for cocoa-stainedfabric) and +6.9 (for coffee/tea-stained fabric) are obtained.

The Alcalase used in the foregoing examples is characterized as having its maximum proteolytic activity at a pH of 8-9. This activity as measured on the commercial enzyme available from Novo lndustri A/S, Copenhagen, Denmark is about 1.5 Anson Units per gram of the enzyme. The commercial enzyme is a raw extract of bacillus subtillis culture and contains about 6 percent of pure crystallized proteolytic material. v

The Monzyme" used in examples 2 and 3 is a mixture of neutral and alkaline proteases (the neutral protease being present in largest amount) containing amylase also; its supplier, Monsanto Chemical Co., states that its proteolytic activity is about 1 million units per gram.

in each of the above examples sodium perborate tetrahydrate is used; other forms of sodium perborate, such as the monohydrate, may be substituted in each case.

The pH of the wash liquor in the foregoing examples, measured in each case after completion of the washing test, is usually within the range of about 8 to about 9.

While the invention finds its greatest utility when sodium perborate is employed, other perborates (such as LiBOgZl-l O, LiBofl-l o, xaomu o or barium or calcium perborates) maybe used in place of all or part'of the sodium per- 9 borate. Also other agents which convert the normally stable activator into a percarboxylic acid (or salt thereof) in the wash water may be used in place of the perborate, e.g., percarbonates or perphosphates.

It is within the broader scope of the invention to use a percarboxylic (i.e., peroxycarboxylic) acid, particularly a solid percarboxylic acid, instead of the combination of perborate and activator. Among such percarboxylic acids are the peroxybenzoic acids, particularly those having chloro or nitro substituents (e.g., m-chloroperoxybenzoic acid, as illustrated in example 6 above, or 2,4-dichloroperoxybenzoic acid). These acids may be protected against deterioration on storage by pelletizing them, preferably with a coating or agglomerating agent such as a low-melting paraffin wax.

As indicated above, the compositions of the invention containing proteolytic enzymes have given outstanding results. Also, as shown in examples 2 and 3, a proteolytic enzyme mixed with an amylase (Monzyme) may also be employed. It is within the broader scope of the invention to use other enzymes in place of, or together with, the proteolytic enzymes. Thus, such stain-attacking enzymes as the amylases (such as the microbial amylases) or other carbohydrases (e.g., maltese saccharase, pectinase, lysozyme, or glycosidases) or the lipases such as microbial lipases, pancreatic lipase, plant lipases or gastric lipase may be used. Specifically, in the composition of example 1A, the Alcalase" may be replaced entirely (or partly) weight-for-weight by either (a) Novo bacterial amylase concentrate having a strength of 397,000 Novo amylase units per gram or (b) Pfizers Lipase P, a pancreatic lipase having a strength of 250 lipase units per gram.

Especially for use in areas where the water has a relatively high heavy metal content, it may often be desirable to have present a compound acting as a stabilizer against an undesirable type of decomposition of the perborate. Among such compounds are the sodium salts of diethylenetriamine pentaacetic acid, ethylene diamine tetra-acetic acid, hydroxyethylethylenediamine triacetic acid or nitrilotriacetic acid. Magnesium silicate may also be present to aid in the stabilizing effect. Minor amounts of these agents, e.g., 5 percent, 1 percent, or less, are effective.

It is to be understood that the foregoing detailed description is merely given by way of illustration and that many variations may be made therein without departing from the spirit of the invention.

1 claim:

1. A process for removing stains from fabrics which comthe following composition has been added in amount sufficient to provide about i to 40 p.p.m. of available oxygen, said composition consisting essentially of effective amounts of an inorganic peroxygen compound, an activator for the peroxygen compound and about 0.001 to 4 percent of a proteolytic enzyme, said peroxygen compound being present in amount to provide about 1 to 40 p.p.m. of available oxygen to the wash water, said activator having a carboxylic acyl group, said peroxygen compound being one which reacts with said activator to form the corresponding percarboxylic acid on addition of said composition to the wash water, said activator being present in amount effective to so convert said peroxygen compound and thereby increase the bleaching effect of said peroxygen compound 'on coffee/tea stains.

2. A process as in claim 1 in which said peroxygen compound is a perborate.

3. A process as in claim 1 in which said peroxygen compound is a perborate and the mol ratio of available oxygen to said activator is about 1:1 to 6: l.

4. Process as in claim 1 in which said activator is -N,N-,N',N'-

'tetra-acetyl ethylenediamine.

5. Process as in claim 1 in which said composition contains sodium perborate and a water-soluble surface-active nonionic detergent and said activator is a m-chlorobenzyol imid'e.

6. A process as in claim 2 in which the perborate is sodium perborateand the activator is selected from the group consista l. ing of a carboxylic ester activator, a carboxylic anhydride activator and a carboxylic acyl amide activator.

7. A process as in claim 3 in which said acyl group is an acetyl group.

8. A process as in claim 3 in which said benzoyl group.

9. A process as in claim 7 in which said enzyme is an extract of Bacillus subtilis culture.

10. A process as in claim 6 in which the activator is a benzoyl compound.

11. A process as in claim 1 in which the activator is a polyacyl amide.

12. A process as in claim 1 in which the activator is a polyacyl amide having a pair of carboxylic acyl groups on a single nitrogen atom.

13. A process as in claim 1 in which the composition contains an organic water-soluble surface-active detergent.

14. A process as in claim 6 in which the composition contains an organic water-soluble surface-active nonionic deteracyl group is a 12. gent 15. A process as in claim 6 in which the composition contains an organic water-soluble surface-active anionic detergent.

16. A process as in claim 6 in which the composition contains at least about one mol of sodium perborate per mol of activator.

17. A process as in claim 10 in which the activator is metachlorobenzoyl dimethylhydantoin.

18. A process as in claim 11 in which the acyl groups are acetyl.

19. A process as in claim 18 in which the activator is N,N,N', N'-tetra-acetylethylenediamine.

20. A process as in claim 13 in which the composition contains a water-soluble builder salt.

21. A process as in claim 20 in which the composition contains pentasodium tripolyphosphate and sodium nitrilotriacetate. 

2. A process as in claim 1 in which said peroxygen compound is a perborate.
 3. A process as in claim 1 in which said peroxygen compound is a perborate and the mol ratio of available oxygen to said activator is about 1:1 to 6:1.
 4. Process as in claim 1 in which said activator is N,N,N'',N''-tetra-acetyl ethylenediamine.
 5. Process as in claim 1 in which said composition contains sodium perborate and a water soluble surface-active nonionic detergent and said activator is a m-chlorobenzyol imide.
 6. A process as in claim 2 in which the perborate is sodium perborate and the activator is selected from the group consisting of a carboxylic ester activator, a carboxylic anhydride activator and a carboxylic acyl amide activator.
 7. A process as in claim 3 in which said acyl group is an acetyl group.
 8. A process as in claim 3 in which said acyl group is a benzoyl group.
 9. A process as in claim 7 in which said enzyme is an extract of Bacillus subtilis culture.
 10. A process as in claim 6 in which the activator is a benzoyl compound.
 11. A process as in claim 1 in which the activator is a polyacyl amide.
 12. A process as in claim 1 in which the activator is a polyacyl amide having a pair of carboxylic acyl groups on a single nitrogen atom.
 13. A process as in claim 1 in which the composition contains an organic water-soluble surface-active detergent.
 14. A process as in claim 6 in which the composition contains an organic water-soluble surface-active nonionic detergent.
 15. A process as in claim 6 in which the composition contains an organic water-soluble surface-active anionic detergent.
 16. A process as in claim 6 in which the composition contains at least about one mol of sodium perborate per mol of activator.
 17. A process as in claIm 10 in which the activator is metachlorobenzoyl dimethylhydantoin.
 18. A process as in claim 11 in which the acyl groups are acetyl.
 19. A process as in claim 18 in which the activator is N,N,N'', N''-tetra-acetylethylenediamine.
 20. A process as in claim 13 in which the composition contains a water-soluble builder salt.
 21. A process as in claim 20 in which the composition contains pentasodium tripolyphosphate and sodium nitrilotriacetate. 